Disposable absorbent articles have been known for many years. They are used for example as sanitary napkins for feminine hygiene, panty liners, children's nappies/diapers or incontinence pads. These disposable absorbent articles share the characteristics that they include a liquid-permeable layer which is disposed towards the wearer's body when the article is in use; a liquid-impermeable layer which is disposed away from the wearer's body when the article is in use; and a liquid-storing layer arranged between these two layers. The liquid-storing layer can for example be made from defiberised cellulose.
The limited liquid-absorption capacity of pure cellulose layers as a liquid-storing material has been a disadvantage with the known disposable absorbent articles. Furthermore, the retention capacity of cellulose, after having been in contact with liquid, is not very pronounced. Finally, deformed cellulose material maintains the shape it has assumed, a fact which is often considered disagreeable by the wearer of the absorbent article. The term ‘wearer’ as used hereinafter can both be male and female.
In addition, disposable absorbent articles are known whose liquid-storing layer contains superabsorbent materials. Superabsorbent materials are able to absorb many times their dry weight of liquid, which they are able to retain to some degree even under pressure load. Superabsorbent materials are for example known from EP-A-0339461.
One difficulty when using superabsorbent materials in the liquid-storing layer of absorbent articles is that superabsorbent materials experience a volume increase when they are in contact with a liquid, i.e. they swell. This leads to the fact that the absorbent article causes a volume increase and to reduced wearer comfort. Furthermore, the individual components of the superabsorbent materials have a tendency to conglutinate after absorbing a liquid. This leads to a pronounced reduction in the theoretically possible liquid-absorption capacity (so-called gel blocking). Gel blocking results in limited distribution of the liquid which has entered the absorbent article. In the case of contact with a substantial amount of liquid, this might lead to the absorbent article no longer being able to completely absorb the liquid in spite of the theoretical storage capacity still being adequate. This leads to the wearer of the article experiencing a feeling of wetness of the skin and thus discomfort and it also leads to the risk of the wearer's garments becoming soiled. Finally, the absorbent article can also experience permanent deformation as a result of the gel blocking effect, thus further reducing wearer comfort of the article.